1. Field of the Invention
The present invention relates to a vehicle having steerable front wheels and steerable rear wheels, and more specifically to a rear wheel steering angle control system arranged to limit a swing motion of a rear end of the vehicle in a direction opposite to a turn direction of the vehicle.
2. Description of the Prior Art
Japanese Patent provisional publication No. 58-97566 shows a conventional steering system for steering both front and rear wheels of a vehicle. When an angular displacement of a steering wheel is greater than a predetermined angle (that is, a small turning radius is required), this steering system steers the rear wheels in a direction opposite to a steering direction of the front wheels in order to reduce the turning radius. If, for example, the driver of a vehicle 30 shown in FIG. 4 starts the vehicle and simultaneously turns front wheels 19 and 20 to the right to move the vehicle in a direction shown by an arrow "A" away from a parking place adjacent to a wall 40, then the steering system of this conventional example turns rear wheels 21 and 22 to the left, and causes a rear end of the vehicle to swing in a leftward direction shown by an arrow "B". Therefore, the rear end bumps against the wall 40.
3. Description of the Related Art
A related U.S. patent application, Ser. No. 703,593, filed on Feb. 20, 1985 shows a steering system arranged to prevent such a collision of a rear end of a four wheel steer vehicle. However, this steering system tends to needlessly deteriorate the steering response of the rear wheels.